Pneumatic control device



an: 17, 1935. I s. SPIESS 2,024,544

PNEUMATIC CONTROL DEVICE G. SPIESS PNEUMATIC CONTROL DEVICE 2Sheets-Shqet 2 Filed Aug. 4, 1954 Patented Dec 17, 1935 PATENT OFFICE2,024,544 PNEUMATIC CONTROL DEVICE Georg Spiess, Leipzig, GermanyApplication August 4,1934, Serial No. 738,565

' In Germany August 5, 1933- V V 2 Claims.

This invention relates to adevice for controlling the conveying of thepile for sheet feed-- ers by means of a suction device comprising acylinder and a piston. The stationary portionof the device is connectedwith an air suction piping, whereas the movable portion thereof,according to the opening or closing of a regulating aperture in thesuction piping at a certainmoment during a sheet separating operation,is differently adjusted at that'momentand thus starts or stops theconveying of the pile according to its adjustment.

A device of this type for controlling the conveying of an adjusted sheetpile to the sheet separating means of a feeder has been proposedalready. 'In this known device the control opening of the suction pipingis arranged in the pile support so as to be covered or released by thefront end of the pile when. the latter recedes owing to the'removal ofthe sheet or is advanced again by the pile conveying means. When thecontrol opening is closed, themovableportion of the sniille device,owing to the vacuum produced in the suction piping, willoccupy aposition involving the stopping of the pile'convey-' ing device, e. g;,of a pawl locking. mechanism,

while, when the control opening is open, the movable portion of thesnifiie device will, under spring tension occupy a position involvingthe startingof the pile conveying means, the change from one position tothe other. depending'solely and that the suction piping of the snifilecyl-' inder contains a control opening which, according to the height.or position of the pile, is closed or opened at a certain moment in thecourse of a sheet separating operation and thus causes the necessary airpressure in the sniffle, cylinder for starting or stopping the pileconveying means. The device according to the invention' may be arrangedso as to have the starting and stopping of the conveying meanscorrespond, respectively, to the opening-and closing of the controlopening, or'vice versa.

As control opening may serve the separating suction nozzle itself and ascontrolling means influenced by the height or position of the pile forclosing ornot closing-the control opening the sheet tobe aspiratedwhich,according'to the height or position of the pile, sooner or, later isdrawn up to the suction nozzle so as to close it at the proper momentwhen the pile is high or advanced enough or, in the other case, to leaveit open. 5

It is, however, preferable to relieve the separating suction nozzle fromthe task to act as regulating opening for the pneumatic control of thepile motion and restrict its function solely to the separation ofsheets. For this reason the invention provides a special control openingin the suction piping leading to thesniifle cylinder and a shut-01fmember for this opening, which is controlled by a feeler testing inknown manner the height or position of the pile between two separatingoperations and which closes or opens the control opening according tothe height or position of the pile, or

establishes or interrupts the connection of the snifile cylinder withthe suction piping ofthe separating suction device. The testing of thesheet pile goes on during the periods when the separating suction devicehas aspirated a sheet and vacuum prevails in the suction piping owing tothe closing of the nozzle; The feeler can thus be combined with theblast which effects the separation of the aspirated sheet from the pileand, according to the invention, is combined therewith in such a waythat the blast serves also as pile feeler and holds the following sheetsin position.

Compared with the known control devices, in which a pile feeler, bymeans of rods, acts directly ion the pile conveying device, thepneumatic transmission of the feeler action to the control mechanism forthe pile transport, as provided by the invention, aifords the advantagethat the power available in the form of the suction pressure in theseparating suction piping is utilized for reversing and the feeler hasto adjust only'a light valve. Furthermore, according to the invention,greater distances be tween the separating device, near which the feeleris preferably disposed, and the control device for the pile transportcan be negotiated without bothersomerods, and the separating device maybe adjusted. These advantages will become especially apparent when thesheets are separated from the pile with their rear edge, as the varioussheet sizes. require the adjustability of the entire separating deviceincluding the feeler. The invention afiords a possibility of combiningthe control opening and the feeler with the separating sucker into anadjustable unit which is not interfered with by the pneu-- s5 maticconnection of the control opening with the snifting cylinder on the onehand and the separating suction piping on the other by a telescopicpiping or flexible tubing.

By way of example, two embodiments of the invention are illustrated inthe accompanying drawings which are restricted to showing the parts of afeeder required for understanding the invention and in which Figure l isa view of one constructional embodiment and Fig. 2, a View of the otherembodiment.

Referring to the drawings, the vertically stacked sheet pile I abutswith its front surface against the guides 2 to the upper ends of whichthe transport bridge 3 is secured over which the sheet 4 is passed tothe roller 5 which in known manner conveys the sheet 4 to the feedingpoint with the aid of pressure rolls, not shown. The sheet 4 isseparated from the pile at its rear edge by a separating suction deviceIt which tilts the aspirated sheet portion and lifts it off from thepile to a certain extent. The mode of operation as well as the means forcontrolling the separating device are known and do not form an object ofthe invention. For this reason, they are not illustated in Fig. l whichshows only an air piping leading from the suction device III to an airpump, not shown, and being designated 25.

To effect the complete separation of the sheet from the pile after therear edge thereof has been raised by the suction device It, air is blownbetween the raised sheet portion and the pile of remaining sheets by ablast H which is controlled so that after the raising of the rear edgeof the sheet it will swing into the gap between the lifted sheet andpile and swing back before another sheet is to be separated.

This blast control is'known also and the device required for it istherefore illustrated only in so far as has to do with the invention.The blast carries out a motion composed of an up and down motion and aswinging motion. The vertical part of the blast pipe H is for thispurpose movably attached to the end of one arm of a bell crank I3oscillatorily arranged at I2. The other arm of the bell crank I3 isarticulated by a rod I4 to one arm of a three-armed lever I9 movablydisposed on the feeder frame and acted upon by a tension spring I5 whichwith its other end is secured to the feeder frame. The spring I6 actsupon the rods I9, I4, I3 to move down the blast II and cause it to reston the top surface of the pile I. This motion of therods I9, I4, I3under the tension of the spring I5 is regulated by a cam plate I8disposed on a single revolution control shaft in the feeder frame andacting with its curved circumference upon a roller l! rctatably disposedon the second arm of the threearmed lever IS. The cam plate I8 and thetension spring I6 thus jointly regulate the up and down motion of theblast II in the course of a sheet separating operation.

The third arm of the three-armed lever I9 is articulated by a rod 29 toa valve 2| which is arranged in a branch air piping 22 turning off fromthe separating suction piping 25 and leading to a snifting cylinder 23secured to the feeder frame. The cam plate It or the surface of the pilelimit the downward motion of the blast II. If the latter is prematurelystopped by the pile during its downward motion, the valve 2I will not bein open position and the snifting piston 24 disposed in known mannerunder spring tension in the snifting cylinder 23 will not be displaced,but remain in the position which it occupies in response to springtension. On the other hand, if the pile falls below, more or less, acertain height, the greater stroke of the blast II acting as pile feelerwill cause the control valve 2I to be lifted more or less from its seatand thus place the inside of the cylinder 23 under the suction pressureof the separating suction piping 25 whereby a displacement of thesnifting piston 24 to the other end position will be effected. Thechange in the position of the snifting piston causes in known manner theactuation of the ratchet gear of the pile transport. The front end ofthe piston rod projecting from snifting cylinder 23 strikes and moves tothe left a locking lever 29 (Fig. 1) whose locking nose is therebywithdrawn from under a locking projection 30 of a control path 8articulated at 28 to the feeder frame and preventing in its operatingposition a pawl I, whose roll 26 moves over the path 8, from engagingthe teeth of the feed gear wheel 9. The pawl 1 is articulated to asector-like feed lever 6' which, by means of the articulated rod I5, isdriven from, a crank disc 38 so as to swing periodically to and fro.When the nose of the locking lever 29 is withdrawn from under theprojection 30 of the control path 8, the free end of the latter willdrop down somewhat and thus permit the pawl I to engage the wheel 9which is thereby moved and caused to raise the pile table to a certainextent in known manner by means of screw spindles, chains or racks, notshown.

By means of a pin 32 a link bar 33 is articulated to the free end of thecontrol path 8 and connected at the other end by means of the slot 34and a pin 35 with a roll arm 36 whose roll 31 moves on the circumferenceof the crank disc 38 constructed as cam plate which, at the proper time,will raise the lowered path 8 into operative position which is securedby the mutual engagement of the nose of the locking lever 29 tensionedby the spring 3| and the locking projection 30. The pawl 1 is thusprevented again from engaging the teeth of the feed wheel 9, theengagement taking place only after the valve 2| has been openedagain bya corresponding lowering of the blast I I and the snifting cylinder 23has been subjected to the suction pressure of the separating suctionpiping.

After the feed wheel 9 has been moved once and before the initialsetting has been reestablished the vacuum in the snifting cylinder 23,simultaneously with the vacuum in the separating suction piping 25, iseliminated by the posi tively and correctly timed opening of a fresh airvalve 2'! in the piping 25. The fresh air valve 21 is opened when thesheet to be fed has reached the roller 5 for the purpose of separatingthe sheet from the separating sucker III.

In the construction shown in Fig. 2 the entire separating deviceincluding the feeler and blast Ila is arranged on a pedestal body 39which is displaceably and fixably disposed on a carrier 40 in thefeeding direction of the sheets. On the body 39 the regulating valve 2Ia is positioned whose casing is connected with the piping 22a leading tothe snifting cylinder 23a. At I2a the lever I3a is disposed whichcontrols the pile feeler Ila constructed as blast and which isarticulated by the rod I4a to the free end of the roll lever I9a whoseroll IIa is drawn by a spring I6a engaging the lever I3a to thecircumference of the cam plate I811. The latter is located on a controlshaft 4| disposed in the body 39 and driven by the worm gear 42 from ashaft 43 extending in the direction of the sheet feed. The shaft 43 isdriven by means of the bevel gears 44 from the main driving shaft 45.

The lever I31 is articulated by a rod 200, to a two-armed lever 20barticulated to the pedestal body 39. The free end of the lever 20bextends below the spindle of the regulating valve 2m held in lockingposition by spring power.

The mode of operation of this device is exactly the same as that of theconstruction described above. r

I claim:

1. A pneumatic device for controlling the pile transport for sheetfeeders comprising a suction head, a suction pipe leading from saidhead, a control valve for said pipe, a feeler independent of said headand adapted to engage the top of the remaining pile upon lifting of thetop sheet from the pile, and means operatively connecting the valve withthe feeler and arranged to raise the valve upon the feeler moving belownormal position.

2. A pneumatic device for controlling the pile transport for sheetfeeders comprising a suction

